Seasonality, labor and integration of aquaculture into southern African smallhold farming systems

Fish production on Malawian smallholdings is generally limited by the quantity and quality of inputs to the pond (Brummett and Noble 1995). The timing of labor availability and other farm activities limit the amount farmers put into their ponds resulting in lower growth rates and yields. There is potential for improving production and yields through modifications of production schedules to accommodate other farming activities. Limited material and labor inputs among farming system enterprises can be better allocated by considering seasonal availability of inputs and adapting the pond and fish farming technology to the farming system. This case from Malawi demonstrates that aquaculture technology that neglects the annual cycle of events and constraints on the farm will not be easily integrated into the farming system. Focusing on technology that maximizes fish production rather than facilitation of adoption and integration has been a feature of the majority of African smallholder agriculture/aquaculture projects. Farming Systems Research (FSR) must identify niches and opportunities for system improvement for it to be worth supporting as a development intervention.

Integration of freshwater prawn culture with rice farming in Kuttanad, India

The integration of paddy cultivation with prawn/fish culture can become a viable alternative to effectively utilize the vast area of derelict polders (embanked coastal flood plains) in Kuttanad, India. Nearly 55 000 ha of wetlands in Kuttanad are available for paddy cultivation year-round. Around 5 000 ha of the polders are utilized for Macrobrachium rosenbergii culture as a follow-up crop. Of the total area, about 250 ha of fallow polders are utilized for monoculture of M. rosenbergii from March to October, while in 4 750 ha polyculture with Indian and exotic carps is practiced from November to June. Stocking density is 15 000 to 60 000/ha for monoculture of M. rosenbergii, while in polyculture with carps, it is 5 000 to 20 000/ha of prawn and 5 000 to 10 000/ha of fish. Production from monoculture varies from 95 to 1 297 kg/ha whereas production from polyculture systems it is 70 to 500 kg/ha of prawn and 200 - 1 200 kg/ha of fish. Profits range from Rs. 5 000 to 20 000/ha. An evaluation is made of how the present polders of Kuttanad are best utilized for culture of M. rosenbergii following different systems of integrated farming and how the integration is useful in the aquaculture sustainability of Kuttanad, a tropical wetland ecosystem.

Integration of crustacean aquaculture with coastal rice farming in Vietnam

Some examples are given of integration of crustacean aquaculture into coastal rice farming in Vietnam. Freshwater prawn (Macrobrachium rosenbergii ) and marine shrimp culture integrated with coastal rice farming and crab (Scylla serrata ) culture in backyard ponds and ricefields are described.

Integration of aquaculture and agriculture: a route to sustainable farming systems

The integration of agriculture and aquaculture as a means of intensifying resource use and improving the productivity of many current farming practices in Southeast Asian and African countries is discussed. A brief account is given of work undertaken by ICLARM in Malawi and India regarding the improved use of marginal lands to integrate crops, vegetables, trees, livestock and fish, outlining also the various problems involved in the extension of such integrated fish farming systems.

Integration of fisheries acoustics surveys and bathymetric mapping to characterize midwater-seafloor habitats of US Virgin Islands and Puerto Rico (2008-2010)

NOAA’s Coral Reef Conservation program (CRCP) develops coral reef management priorities by bringing together various partners to better understand threats to coral reef ecosystems with the goal of conserving, protecting and restoring these resources. Place-based and ecosystem-based management approaches employed by CRCP require that spatially explicit information about benthic habitats and fish utilization are available to characterize coral reef ecosystems and set conservation priorities. To accomplish this, seafloor habitat mapping of coral reefs around the U.S. Virgin Islands (USVI) and Puerto Rico has been ongoing since 2004. In 2008, fishery acoustics surveys were added to NOAA survey missions in the USVI and Puerto Rico to assess fish distribution and abundance in relation to benthic habitats in high priority conservation areas. NOAA’s National Centers for Coastal Ocean Science (NCCOS) have developed fisheries acoustics survey capabilities onboard the NOAA ship Nancy Foster to complement the CRCP seafloor habitat mapping effort spearheaded by the Center for Coastal Monitoring and Assessment Biogeography Branch (CCMA-BB). The integration of these activities has evolved on the Nancy Foster over the three years summarized in this report. A strategy for improved operations and products has emerged over that time. Not only has the concurrent operation of multibeam and fisheries acoustics surveys been beneficial in terms of optimizing ship time and resources, this joint effort has advanced an integrated approach to characterizing bottom and mid-water habitats and the fishes associated with them. CCMA conducts multibeam surveys to systematically map and characterize coral reef ecosystems, resulting in products such as high resolution bathymetric maps, backscatter information, and benthic habitat classification maps. These products focus on benthic features and live bottom habitats associated with them. NCCOS Centers (the Center for Coastal Fisheries and Habitat Research and the Center for Coastal Environmental Health and Biomolecular Research) characterize coral reef ecosystems by using fisheries acoustics methods to capture biological information through the entire water column. Spatially-explicit information on marine resources derived from fisheries acoustics surveys, such as maps of fish density, supports marine spatial planning strategies and decision making by providing a biological metric for evaluating coral reef ecosystems and assessing impacts from pollution, fishing pressure, and climate change. Data from fisheries acoustics surveys address management needs by providing a measure of biomass in management areas, detecting spatial and temporal responses in distribution relative to natural and anthropogenic impacts, and identifying hotspots that support high fish abundance or fish aggregations. Fisheries acoustics surveys conducted alongside multibeam mapping efforts inherently couple water column data with information on benthic habitats and provide information on the heterogeneity of both benthic habitats and biota in the water column. Building on this information serves to inform resource managers regarding how fishes are organized around habitat structure and the scale at which these relationships are important. Where resource managers require place-based assessments regarding the location of critical habitats along with high abundances of fish, concurrent multibeam and fisheries acoustics surveys serve as an important tool for characterizing and prioritizing coral reef ecosystems. This report summarizes the evolution of fisheries acoustics surveys onboard the NOAA ship Nancy Foster from 2008 to 2010, in conjunction with multibeam data collection, aimed at characterizing benthic and mid-water habitats in high priority conservation areas around the USVI and Puerto Rico. It also serves as a resource for the continued development of consistent data products derived from acoustic surveys. By focusing on the activities of 2010, this report highlights the progress made to date and illustrates the potential application of fisheries data derived from acoustic surveys to the management of coral reef ecosystems.

Integration of data for nowcasting of harmful algal blooms

Harmful algal blooms (HABs) are a significant and potentially expanding problem around the world. Resource management and public health protection require sufficient information to reduce the impacts of HABs by response strategies and through warnings and advisories. To be effective, these programs can best be served by an integration of improved detection methods with both evolving monitoring systems and new communications capabilities. Data sets are typically collected from a variety of sources, these can be considered as several types: point data, such as water samples; transects, such as from shipboard continuous sampling; and synoptic, such as from satellite imagery. Generation of a field of the HAB distribution requires all of these sampling approaches. This means that the data sets need to be interpreted and analyzed with each other to create the field or distribution of the HAB. The HAB field is also a necessary input into models that forecast blooms. Several systems have developed strategies that demonstrate these approaches. These range from data sets collected at key sites, such as swimming beaches, to automated collection systems, to integration of interpreted satellite data. Improved data collection, particularly in speed and cost, will be one of the advances of the next few years. Methods to improve creation of the HAB field from the variety of data types will be necessary for routine nowcasting and forecasting of HABs.

Integration of submersible transect data and high-resolution multibeam sonar imagery for a habitat-based groundfish assessment of Heceta Bank, Oregon

In the face of dramatic declines in groundfish populations and a lack of sufficient stock assessment information, a need has arisen for new methods of assessing groundfish populations. We describe the integration of seafloor transect data gathered by a manned submersible with high-resolution sonar imagery to produce a habitat-based stock assessment system for groundfish. The data sets used in this study were collected from Heceta Bank, Oregon, and were derived from 42 submersible dives (1988–90) and a multibeam sonar survey (1998). The submersible habitat survey investigated seafloor topography and groundfish abundance along 30-minute transects over six predetermined stations and found a statistical relationship between habitat variability and groundfish distribution and abundance. These transects were analyzed in a geographic information system (GIS) by using dynamic segmentation to display changes in habitat along the transects. We used the submersible data to extrapolate fish abundance within uniform habitat patches over broad areas of the bank by means of a habitat classification based on the sonar imagery. After applying a navigation correction to the submersible-based habitat segments, a good correlation with major boundaries on the backscatter and topographic boundaries on the imagery were apparent. Extrapolation of the extent of uniform habitats was made in the vicinity of the dive stations and a preliminary stock assessment of several species of demersal fish was calculated. Such a habitat-based approach will allow researchers to characterize marine communities over large areas of the seafloor.